The present invention relates to ink fixing materials and methods for fixing dye based inks to solid and porous substrates, for example, walls and fabrics.
Direct inkjet printing onto a variety of substrates such as films, papers, and fabrics has been used to generate graphic images. However, for substrates that are either of poor dimensional stability (such as many fabrics), or that are too large to be handled using a conventional inkjet printer (for example, a wall of a room), indirect printing methods such as transfer printing methods are normally employed. Current inkjet transfer printing methods include printing onto fabrics that have adhesive backings adhering them to a release liner, or iron-on transfers.
Inkjet printing has been used to provide images on a wide variety of substrates including films, papers, fabrics, and the like. Commercially available inks for inkjet printers are typically aqueous based and employ dyes as colorants. Current commercially available inks generally lack the simultaneous properties of good image quality (e.g., high resolution and color density) and waterfastness or washfastness when printed on any of the above-mentioned substrates. This is important if the image is transferred to a surface that will encounter water or be washed in normal usage (for example, clothing, room walls, etc.).
Whether inkjet printing is performed in an industrial process or on a printer attached to a personal computer, there exists a need to be able to print an image on a wide variety of substrates that have the simultaneous properties of good image quality and waterfastness or even washfastness.
The present invention provides compositions and processes useful for improving image quality and water resistance of dye based ink images, particularly dye based inks used in inkjet printing. The compositions and processes are easy to use and suitable for office and home use environments.
In one aspect, the invention provides a method for providing a durable ink image on a substrate. The method comprises the steps of coating a surface of the substrate with an aqueous mordant dispersion; printing or transferring a selected image onto the coated surface; optionally drying the image; applying a dispersed hydrophobic material onto the imaged surface; and drying the dispersed hydrophobic material. The method may optionally further include the step of heating the transferred and fixed image. The method may also optionally include the step of drying the coated mordant dispersion before printing or transferring the image.
In another aspect, the invention provides another method for providing a durable ink image on a substrate. The method comprises the steps of coating a surface of the substrate with an ink fixing mixture comprising an aqueous dispersion of a mordant and a dispersed hydrophobic material; printing or transferring a selected image onto the coated substrate; and drying the image and coated ink fixing mixture. The method may further include the step of heating the transferred and fixed image.
In another aspect, the invention provides a method for providing a durable ink image on a non-porous substrate. The method comprises the steps of coating a surface of a non-porous substrate with an aqueous fluoropolymer dispersion, printing or transferring an image onto the coated non-porous substrate; and heating the coated image. The method may also optionally include drying the coated fluoropolymer dispersion at ambient temperature prior to printing or transferring the image.
In still another aspect, image bearing articles are provided that are prepared by any of the preceding methods.
In still an another aspect, the invention provides a kit for providing a durable image on a substrate. The kit comprises an image transfer medium, aqueous mordant dispersion, and hydrophobic material dispersion. The mordant dispersion and hydrophobic material dispersions may be supplied separately or as a mixture of the two.
A feature of the invention is that it provides materials and means whereby aqueous inkjet inks may be printed with high resolution and good color density, and having improved waterfastness and washfastness compared to prior methods.
The term xe2x80x9cmordantxe2x80x9d means a compound which, when present in a composition, interacts with a dye to prevent diffusion through the composition.
A xe2x80x9cnon-porous substratexe2x80x9d is a substrate that is not porous to ink.
As used herein, the term xe2x80x9cdryxe2x80x9d refers to dry to the touch; that is, does not transfer to a finger when touched.